It was this:
A promoted tweet (I don't follow the Liberal Victoria Twitter account) attacking Labor.
There are several things going on here.
First, this was simply the latest in a stream of promoted tweets from @LiberalVictoria that have found their way into my Twitter timeline. Every single one has been an attack on Labor; not one has pushed their own case, talked about their achievements, pumped up their own people.
Not one. You'd think that after 4 years in government, they'd have something to say about their own party... but no. Instead, it's relentless negativity.
Then there's the content of the tweet itself. "Labor has been caught rorting YOUR money."
Look up the article depicted in the tweet. It's from the Herald Sun, dated 6 October 2014. It tells how Labor has spent taxpayer money on polls, and ads, and a social media consultant.
There is no suggestion of impropriety. No one from the Liberal party was interviewed or quoted. No rules were broken, no guidelines ignored. It's a startlingly dull article that goes nowhere, and was only written because the Herald Sun made a Freedom of Information request about the spending.
There was no corresponding article about Liberal spending in the Herald Sun. No Freedom of Information request for Liberal details. That's also not surprising, given who owns the Herald Sun.
Contrast this with the Liberal party's own taxpayer-funded advertising campaign. The Napthine government has been accused again and again of using huge sums of taxpayer money to fund overtly political advertising campaigns, in breach of electoral regulations.
The Opposition, via Shadow Attorney-General Martin Pakula, has not only been vocal in his condemnation of the government's tactics, but has formally complained to the state's financial watchdog.
And it's been estimated that while Labor's campaign has been a low-cost, grass-roots affair, the Liberal advertising blitz will end up costing close to $10 million. That's the view, not only from Labor:
It's clear that it's the Liberal party that has been spending up big in the lead up to the state election. There are billboards on every corner, signs on every fence, ads on every channel and leaflets in every letterbox. Yet @LiberalVictoria, the official and verified Victorian Liberal Twitter account, says Labor is to blame.
And that brings me to the final irony of this little mess.
One of the Labor costs listed in that Herald Sun article was approximately $50,000 spent on a US-based political campaign expert to provide guidance in matters concerning social media.
Compare Labor's restrained presence on social media on the past few months, the way they've focused on their own people, their own promises and their own actions, with the frothing "attack and demean" tactics that the Liberal party has employed on social media.
I'd say $50,000 was money well spent. Labor has learned a lot of lessons, and this was one of them.
Whereas the Liberals haven't learned a damned thing. And that's why they'll lose on November 29.